1. Field of the Invention
The present invention relates to a fixing device for use in a copier, facsimile apparatus, printer or similar electrophotographic image forming apparatus and more particularly to control over power supply for a cleaning mechanism configured to remove toner deposited on a heat roller included in a fixing device.
2. Description of the Background Art
While a fixing device included in an image forming apparatus is configured to fix a toner image on a sheet or recording medium with a heat roller, it is likely that part of the toner image is not fixed on the sheet, but is deposited on a peeler adapted for peeling off the sheet from the heat roller. The toner thus deposited on the peeler is apt to form lumps and suddenly drop onto the heat roller, smearing successive sheets. In order to solve this problem, the fixing device is usually provided with a cleaning mechanism for removing the toner deposited on the heat roller.
On the other hand, energy-saving schemes have recently been applied to various kinds of apparatuses in order to cope with environmental problems. An image forming apparatus, for example, is required to immediately turn off power supply as soon as a printing operation ends after fixing a toner image on a sheet. However, because the cleaning mechanism of the fixing device is configured to clean the heat roller after a printing operation, as stated previously, turning off power supply immediately after a printing operation causes the cleaning operation to be interrupted halfway or practically prevented from being executed.
Technologies relating to the present invention are disclosed in, e.g., Japanese Patent Laid-Open Publication No. 07-104602 and Japanese Patent No. 3,514,134.